1. Field of the Invention
The present invention relates to a bed and, more particularly, to a bed used in, e.g., medical applications and the like.
2. Related Background Art
People who are confined to bed from various reasons rarely move their bodies and thus tend to cause bedsores. A bedsore refers to a necrotic state that occurs to a skin or soft tissue of a portion, where a bone projects, of a patient who is confined to bed for a long period of time, as a result of circulatory malady when the skin or tissue is pressed between the bone and the bed over a long period of time.
For example, a water bed 1 is conventionally used to prevent a bedsore. In the water bed 1, as shown in FIG. 7, a water bag 20 filled with water 22 is supported by a bed frame 30. A heater 40 having a thermostat is attached to the side portion of the water bag 20. When a bed user 100, e.g., a patient who is confined to bed, lies on the water bed 1, a uniform force acts on the contact portion of the water bag 20 and the bed user 100, so that no bedsore occurs easily. In addition, the bed user 100 can sleep comfortably.
However, as the causes of bedsore, in addition to the pressure described above, bacterial infection must not be forgotten. Therefore, currently, a bedsore is prevented by, e.g., cleaning a bed-confined patient with alcohol by a person in charge of nursing.
In the bed-confined state, a decrease in bone mass occurs to the bed user 100. When the bone mass decreases, porosity occurs in the bone likely to cause osteoporosis finally. As a result, the patient tends to suffer a fracture during care, which will cause bed confinement in turn, leading to a vicious cycle.
It is said that, at present, there are 4 million people in Japan who are confined to bed. As the percentage of aged people increases in the future, the number of bed-confined patients will increase, leading to an increase in medical cost.